/**
 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS HEADER.
 *
 * Copyright (c) 1997-2010 Oracle and/or its affiliates. All rights reserved.
 * Portions Copyright 2013-2018 Philip Helger + contributors
 *
 * The contents of this file are subject to the terms of either the GNU
 * General Public License Version 2 only ("GPL") or the Common Development
 * and Distribution License("CDDL") (collectively, the "License").  You
 * may not use this file except in compliance with the License.  You can
 * obtain a copy of the License at
 * https://glassfish.dev.java.net/public/CDDL+GPL_1_1.html
 * or packager/legal/LICENSE.txt.  See the License for the specific
 * language governing permissions and limitations under the License.
 *
 * When distributing the software, include this License Header Notice in each
 * file and include the License file at packager/legal/LICENSE.txt.
 *
 * GPL Classpath Exception:
 * Oracle designates this particular file as subject to the "Classpath"
 * exception as provided by Oracle in the GPL Version 2 section of the License
 * file that accompanied this code.
 *
 * Modifications:
 * If applicable, add the following below the License Header, with the fields
 * enclosed by brackets [] replaced by your own identifying information:
 * "Portions Copyright [year] [name of copyright owner]"
 *
 * Contributor(s):
 * If you wish your version of this file to be governed by only the CDDL or
 * only the GPL Version 2, indicate your decision by adding "[Contributor]
 * elects to include this software in this distribution under the [CDDL or GPL
 * Version 2] license."  If you don't indicate a single choice of license, a
 * recipient has the option to distribute your version of this file under
 * either the CDDL, the GPL Version 2 or to extend the choice of license to
 * its licensees as provided above.  However, if you add GPL Version 2 code
 * and therefore, elected the GPL Version 2 license, then the option applies
 * only if the new code is made subject to such option by the copyright
 * holder.
 */
package com.helger.jcodemodel.util;

import java.security.AccessController;
import java.security.PrivilegedAction;

/**
 * Class defined for safe calls of getClassLoader methods of any kind
 * (context/system/class classloader. This MUST be package private and defined
 * in every package which uses such invocations.
 *
 * @author snajper
 */
public final class JCSecureLoader
{
  private JCSecureLoader ()
  {}

  public static ClassLoader getContextClassLoader ()
  {
    if (System.getSecurityManager () == null)
    {
      return Thread.currentThread ().getContextClassLoader ();
    }
    return AccessController.doPrivileged ((PrivilegedAction <ClassLoader>) () -> Thread.currentThread ()
                                                                                       .getContextClassLoader ());
  }

  public static ClassLoader getClassClassLoader (final Class <?> c)
  {
    if (System.getSecurityManager () == null)
    {
      return c.getClassLoader ();
    }
    return AccessController.doPrivileged ((PrivilegedAction <ClassLoader>) () -> c.getClassLoader ());
  }

  public static ClassLoader getSystemClassLoader ()
  {
    if (System.getSecurityManager () == null)
    {
      return ClassLoader.getSystemClassLoader ();
    }
    return AccessController.doPrivileged ((PrivilegedAction <ClassLoader>) () -> ClassLoader.getSystemClassLoader ());
  }

  public static void setContextClassLoader (final ClassLoader cl)
  {
    if (System.getSecurityManager () == null)
    {
      Thread.currentThread ().setContextClassLoader (cl);
    }
    AccessController.doPrivileged ((PrivilegedAction <Object>) () -> {
      Thread.currentThread ().setContextClassLoader (cl);
      return null;
    });
  }
}
